#include<stdio.h>
double fact(double s)
{
double i,a = 1;
for (i = 1;i<=s;i++) 
a = a*i;
return a;
}
int main()
{
double x,y,m,n;
scanf("%lf",&m);
scanf("%lf",&n);
y = fact(n-m);
m = fact(m);
n = fact(n);
x = n/(y*m);
printf("result = %.0f",x);
return 0;
} 
